Azo dye for lakes.



- UNITED S A ES PATENT -OFFICE.

PAUL JULIUS, or LUDWIGSHAFEN, GERMANY, ASSIGNOR TO THE BADiSFi-IE ANILIN AND SODA FABRIK, OF -SAME PLACE.

AZO'DYEFOR LAKES.

SPECIFICATION forming part of Letters Patent 210.650,?57, dated May 29, 1900. Application and January 10,1900. Serial No. 901. (Specimens) Toyall whom it mag concern;

Be it known that I, PAUL JULIUS, doctor of philosophy, a subject of the Emperor of Ausaria-Hungary, residing at Ludwigshafen-onthe-Rhine, in the Kingdom of-Bava'ria, Germany, have invented new and useful Improvements in the Manufacture of a New Monoazo Coloring lllatter, of which the following is a specification.

My inventioniconsists in the product-ionof a new mono-azo coloring-matter which derives its especial value from the fact that it in the form of its salts with several of the -metals is insoluble .or practically insoluble in water, so that they can be used as colored printing-lakes in lithography,- in the manufacture of colored papers and of'paints' with oils, and for similar purposes.

My new azodye is obtained by diazotizing 2-naphthy1amin-l sulfoacid and combining the diazo compound thus obtained with betanaphthol. Already in the form of its free acid my new coloring-matter is characterized .to a'striking degree by its sparing solubility .in water in that it is almost insoluble in cold water and somewhat soluble in boilingwater.-

The alkali salts are less soluble .in hot water than the free acid, and in the form of such salts as those with calcium, barium, aluminum, and lead' the new coloring-matter is practically insoluble even in boiling water. These salts possess a red color and are fast against the action of acids and light and do not sublime, as is the case with many insoluble azo dyes. I

The chemical characteristics by which my coloring-matter can best be recognized are as follows: On reduction the Z-naphthylamimlsulfoacid is obtained, and this on prolonged boiling in acid solution yields beta-naphthylamm.

0n treating my new coloring-matter with concentrated sulfuric acid it yields a brilliant red-violet color.

The following example will serve to further illustrate the manner in which my invention can'best be carried into practical efiect and my new coloring-matter obtained. V x Example: Dissolve about two hundred and twenty-three (223) parts of 2-naphthyla-minl-sulfoacid in about one thousand (1,000)

NaOI-I. 'stantaneously. Boil-the mixture, filter hot,

salt.

parts of water containing about one hundred and twenty (120) parts of caustic-soda lye containing thirty five per cent. NaOH. To this add a solution of sixty-nine (69) parts 0t sodium nitrite. Run the mixed solutions into a mixture of three hundred and fifty (350) parts of hydrochloric acid'tcontaiuing about thirty per cent. H01) with an equal volume of water. Stir while mixing and continue stirring until the production of the diazo conipound is completed. The diazo compound separates out almost completely as a sulfuryellow crystalline precipitate. Collect by filtering, mix the crystalline mass with a little water to form a paste, and pour this paste into asolution of about one hundred and fifty (150) parts of beta-naphthol in four hundred parts (400) parts of watercontaining about one hundred 'and'twenty (120) parts of caustic-soda lye containing about; thirty/five per cent.

The union takes place almost inpress, and dry. In this way my new coloringmatter is obtained in the form of its sodium In order to obtain it as the free. acid, after pressing the sodium salt, but before dryiug,.stir the press-cake with water to a paste and add hydrochloric acid. Filter and wash "the color till sufficiently free from hydrohloric acid.

My new coloring-matter can be obtained in the form of its salts with the other metals mentioned by double decomposition of the sodium salt with the soluble-salts of the other metals or by boiling the free acid with the salts of these metals, if necessary, in the presence of their carbonates or of other agents for binding the free acid formed. If desired, these combinations can be effected in the pres .ence of a substratum or base, such as is used for lakes, or under such conditions that the substratu m or base forms simultaneously with the lakes. As instances of such substrate. or bases I mention barium sulfate, lead sulfate, and aluminum hydrdiid.

Now what I claim is r The mono-azo coloring-matter which can be 1 obtained by diazotizing 2-naphthylamin-1-sulfo'acid and combining the diazo compound with beta-naphthol and which in the form of its calcium, barium,, lead, and alumina salts is practically insoluble in boiling water and In testimony whereof I have hereunto set which on reduction with stannons chlorid my hand in the presence of two subscnbmg yields a naphthylamin sulfoacid which on witnesses.

boiling in acid solution is converted into beta- PAUL JULIUS- 5 napht-hylamin and which gives a rcdwiolet Witnesses:

color with concentrated sulfuric sold, all sul ERNEST EHIRHARDT,

stantially as described. OSCAR BALLY. 

